BOGOTA, Colombia — In a move that has raised expectations here that fugitive drug kingpin Pablo Escobar soon will give himself up, Escobar's brother and two men suspected of leading the Medellin cartel's terrorism units surrendered on Thursday.

Roberto Escobar, Jhon Jairo Velasquez and Otoniel Gonzalez were among nine cartel members who escaped with the notorious cocaine czar from a luxury prison in July, when authorities tried to transfer them to a more secure facility.

After surrendering to authorities in the Medellin suburb of Itagui, the three fugitives were taken Thursday to a high-security prison built especially to house cartel members, a judicial report said.

They are sharing a cellblock with another cartel underling who surrendered again on Sept. 16 and three other prisoners, who are accused of helping Escobar direct his cocaine trafficking organization.

Noting that a series of cartel henchmen also gave up in similar fashion before Escobar surrendered in June, 1991, Juan Gomez Martinez, governor of Antioquia state, said of the latest moves in the state capital of Medellin, "I expect that this is the step preceding the re-surrender of Pablo Escobar."

President Cesar Gaviria was told of the surrenders while testifying before a congressional committee investigating Escobar's escape. Several of Gaviria's congressional supporters told reporters that the moves vindicate Gaviria's policy of offering drug suspects leniency in exchange for their surrender.

But critics maintain that the policy allowed Escobar to dictate the terms of his first confinement and may do so again. His jail overlooking Medellin included such luxuries as a Jacuzzi, fax and computer equipment. Critics also argue that attempts to appease drug terrorists only result in more violence.

Indeed, officials in Medellin now accuse Escobar of re-initiating a terrorist campaign against police like the one that left more than 300 officers dead in 1990. Gunmen allegedly working for Escobar have killed 19 police detectives since the campaign began on Sept. 10.

"The agents' deaths were ordered by the escapees, who seek to discourage security forces from carrying out the mission to capture them," Gen. Miguel Gomez Padilla, the head of the national police, said recently. Gustavo de Greiff, the country's chief prosecutor, froze several Bogota bank accounts earlier this week, saying the cartel was using them to pay for assassinations of top Colombian officials.

But Thursday's surrenders indicate that Escobar may be finding it harder to win this latest bloody round. Not only is the government fulfilling its pledge to jail surrendering cartel members in the new, more secure prison in Itagui, but Escobar and his men also face more pressure as they try to hide from their enemies.

Velasquez indirectly acknowledged in a television interview after his surrender that the cartel's enemies now include not just police but rival criminals who know Medellin's back alleys and hillside slums well.

Authorities say Escobar and his men have enraged the Itagui cartel, a vicious gang of Medellin traffickers. Weeks before his escape, a group allegedly working for Escobar tortured and killed two sets of brothers, Gerardo and William Moncada and Mauricio and Fernando Galeano, along with 18 of their men.

The brothers, based in Itagui, had grown wealthy and powerful working for Escobar. But they reportedly angered their boss by refusing to give him a bigger cut of their cocaine profits.

Sources in Medellin's northeastern neighborhoods, where several terrorist gangs are based, say that a surviving Galeano brother, Rafael, has offered a $1.5-million bounty for Escobar. This sum comes atop the American and Colombian government offers of a total of $3.9 million for information leading to his capture.